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Some Local-Global Principles for Formally Real Fields

Published online by Cambridge University Press:  20 November 2018

M. Marshall
M. Marshall*
Affiliation:
University of Saskatchewan, Saskatoon, Saskatchewan
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Abstract

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Let F be a formally real field, and let A be a preordering of F; that is, a subset of F satisfying Δ + Δ = Δ, Δ Δ = Δ, F2 ⊆ Δ. Denote by X Δ the set of all orderings P of F satisfying P ⊇ Δ. Thus Δ = ⋂ p ∈xΔP. This result is well known. It was first proved by Artin [3, Satz 1] in the case Δ = ∑ F2.

Type
Research Article
Information
Canadian Journal of Mathematics , Volume 29 , Issue 3 , 01 June 1977 , pp. 606 - 614
Copyright
Copyright © Canadian Mathematical Society 1977

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